Davis was originally cast as an extra Ewok, but when Kenny Baker, who was originally going to be Wicket, fell ill, George Lucas picked Davis to be the new Wicket after seeing how he carried himself as an Ewok.[3] Davis based his Ewok movements on his dog, who would tilt his head from side to side whenever he saw something strange. During production on the film, Davis was the subject of a short mockumentary film about his experience as Wicket, titled Return of the Ewok, made by Return of the Jedi's first assistant director, David Tomblin. The unreleased film was a fictional look at his decision to become an actor and act in the film and his transformation into Wicket the Ewok. Davis reprised his role as Wicket in the ABC made-for-TV films Caravan of Courage: An Ewok Adventure and Ewoks: The Battle for Endor.

Davis played the role of Professor Filius Flitwick in the Harry Potter films.[6] Davis played a white-moustached Flitwick in the first two films, and then a black-haired unnamed chorus conductor for the third installment of the series. In the fourth film, Flitwick is younger looking, with short, brown hair and a trimmed moustache. In addition to playing Flitwick, Davis played the role of the goblin Griphook in Harry Potter and the Deathly Hallows, despite the role being played previously by fellow dwarf actor Verne Troyer.

In March 2013, Davis presented an episode of the ITV series Perspectives: Warwick Davis – The Seven Dwarfs of Auschwitz, in which he explored the story of the Ovitz family, a touring musical troupe which included seven dwarfs who survived the NaziAuschwitz concentration camp and the experiments of Josef Mengele.

In 2014, Davis hosted a factual series for ITV called Weekend Escapes with Warwick Davis. The show saw Davis and his family travelling around Britain, enjoying short weekend holiday breaks.[12] The show returned for a second series in spring 2015.

Since 2014, Davis has hosted the revived version of game show Celebrity Squares on ITV. The first series was shown in 2014 and a second aired in 2015.[13]

In addition to his acting career, in 1995, Davis co-founded, with fellow dwarf actor and father-in-law Peter Burroughs, the talent agency Willow Management, that specialises in representing actors under five feet tall. Many of Davis's co-stars and fellow dwarf actors from Star Wars, Willow, Labyrinth and the Harry Potter series are represented by the agency. In 2004, the agency also began representing actors over seven feet tall who had also suffered from being confined to "niche" roles. Over 40 members of Willow Management were cast as goblins in Harry Potter and the Deathly Hallows – Part 2. In April 2010, Davis published his autobiography, Size Matters Not: The Extraordinary Life and Career of Warwick Davis, with a foreword by George Lucas.[15] In January 2013, he appeared in a Comic Relief episode of The Great British Bake Off, winning that episode's title of "Comic Relief Star Baker".

Davis is a founder of the Reduced Height Theatre Company, which stages theatrical productions cast exclusively with short actors and using reduced height sets. Their first production was See How They Run, touring the UK in 2014.[16] In February 2015 the production was the subject of the BBC's "Warwick Davis' Big Night" as part of the Modern Times documentary series.[17]

Unlike most dwarfs (70%) who have a condition called achondroplasia, Davis' dwarfism is caused by an extremely rare genetic condition called spondyloepiphyseal dysplasia congenita (SED). He has said the only real drawback to being small was the associated health problems. Of his own dwarfism, Davis has said, "As you get older, you can suffer from painful hips, and our joints wear a lot quicker than for people of average height".[citation needed]

Davis is married to Samantha Burroughs (b.1971) and they have two children, a daughter Annabelle and a son Harrison.[18] They live in Holme near Peterborough, Cambridgeshire. Annabelle stars in the CBBC show, The Dumping Ground.

Davis' wife, Samantha has achondroplasia and their two children also have SED.[19] As a result of having different causes of dwarfism, the couple's two older sons, Lloyd and George, died shortly after birth, having had a fatal combination of the conditions.[20] Samantha is the daughter of his business partner Peter Burroughs, and the sister of actress Hayley Burroughs. Davis met the Burroughs family while filming Willow, where they had minor roles as Nelwyn villagers.[21]